Bundle-Activator CLASS

private void verifyActivator() throws Exception {
	String bactivator = main.get(Constants.BUNDLE_ACTIVATOR);
	if (bactivator != null) {
		TypeRef ref = analyzer.getTypeRefFromFQN(bactivator);
		if (analyzer.getClassspace().containsKey(ref)) {
			Clazz activatorClazz = analyzer.getClassspace().get(ref);

			if (activatorClazz.isInterface()) {
				registerActivatorErrorLocation(error("The Bundle Activator " + bactivator +
						" is an interface and therefore cannot be instantiated."),
						bactivator, ActivatorErrorType.IS_INTERFACE);
			} else {
				if(activatorClazz.isAbstract()) {
					registerActivatorErrorLocation(error("The Bundle Activator " + bactivator +
							" is abstract and therefore cannot be instantiated."),
							bactivator, ActivatorErrorType.IS_ABSTRACT);
				}
				if(!activatorClazz.isPublic()) {
					registerActivatorErrorLocation(error("Bundle Activator classes must be public, and " +
							bactivator + " is not."), bactivator, ActivatorErrorType.NOT_PUBLIC);
				}
				if(!activatorClazz.hasPublicNoArgsConstructor()) {
					registerActivatorErrorLocation(error("Bundle Activator classes must have a public zero-argument constructor and " +
							bactivator + " does not."), bactivator, ActivatorErrorType.NO_SUITABLE_CONSTRUCTOR);
				}

				if (!activatorClazz.is(QUERY.IMPLEMENTS,
						new Instruction("org.osgi.framework.BundleActivator"), analyzer)) {
					registerActivatorErrorLocation(error("The Bundle Activator " + bactivator +
							" does not implement BundleActivator."), bactivator, ActivatorErrorType.NOT_AN_ACTIVATOR);
				}
			}
			return;
		}

		PackageRef packageRef = ref.getPackageRef();
		if (packageRef.isDefaultPackage())
			registerActivatorErrorLocation(error("The Bundle Activator is not in the bundle and it is in the default package "),
					bactivator, ActivatorErrorType.DEFAULT_PACKAGE);
		else if (!analyzer.isImported(packageRef)) {
			registerActivatorErrorLocation(error(Constants.BUNDLE_ACTIVATOR +
					" not found on the bundle class path nor in imports: " + bactivator),
					bactivator, ActivatorErrorType.NOT_ACCESSIBLE);
		} else {
			registerActivatorErrorLocation(warning(Constants.BUNDLE_ACTIVATOR + " " + bactivator +
					" is being imported into the bundle rather than being contained inside it. This is usually a bundle packaging error"),
					bactivator, ActivatorErrorType.IS_IMPORTED);
		}
	}
}




			String s = getProperty(BUNDLE_ACTIVATOR);
		if (s != null) {
			activator = getTypeRefFromFQN(s);
			referTo(activator);
			trace("activator %s %s", s, activator);
		}